When your dog is throwing up and has diarrhea at the same time, it’s a clear sign that something is not right with their digestive system.
While the occasional upset stomach isn’t uncommon in dogs, the combination of vomiting and diarrhea may point to something more serious.
Understanding why your dog is throwing up and has diarrhea is essential to identifying whether it’s a simple digestive upset or a sign of a more serious condition that requires veterinary intervention.
What it Means When Your Dog is Throwing Up and Has Diarrhea
Dog throwing up and diarrhea often happen due to irritation or inflammation of the gastrointestinal tract, which can be triggered by infections, dietary indiscretion, food allergies, toxins, stress, or underlying medical conditions like pancreatitis or kidney disease.
These symptoms occur when the stomach and intestines attempt to expel harmful substances or react to internal imbalances.
While occasional episodes may not be serious, persistent vomiting and diarrhea can lead to dehydration and signal a more serious issue.
Common Causes of Dog Throwing Up and Diarrhea
1. Gastrointestinal Infections
Bacterial, viral, or parasitic infections are some of the leading causes of dog throwing up and diarrhea.
Viruses like parvovirus, distemper, or rotavirus, and bacteria such as Salmonella or E. coli can severely disrupt the digestive tract.
Dogs with intestinal parasites like hookworms, giardia, or roundworms can also experience these symptoms.
These infections irritate the GI lining, causing inflammation that leads to vomiting and loose, watery stools.
In some cases, the dog may also have a fever, loss of appetite, and lethargy.
Puppies, unvaccinated dogs, and immunocompromised pets are more susceptible to these infections.
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2. Dietary Indiscretion
Dogs are notorious for eating things they shouldn’t—garbage, spoiled food, or foreign objects.
This behavior, known as dietary indiscretion, can lead to dog throwing up and diarrhea.
A sudden change in diet or eating table scraps that are too rich or spicy can also upset your dog’s stomach.
When your dog eats something they can’t digest, their body tries to expel it by vomiting.
If it passes into the intestines, it may cause inflammation resulting in diarrhea.
This is usually temporary but can become serious if vomiting and diarrhea are prolonged.
3. Food Allergies or Sensitivities
Some dogs develop food allergies or sensitivities to specific ingredients like beef, chicken, dairy, or grains.
These sensitivities can irritate the gut lining, causing your dog to throw up and experience diarrhea regularly.
This type of reaction may also come with itchy skin, frequent ear infections, and chronic paw licking.
Identifying and eliminating the offending ingredient from your dog’s diet can help resolve the symptoms.
4. Ingestion of Toxins
Toxic substances such as chocolate, certain houseplants, human medications, pesticides, and cleaning products can cause sudden dog throwing up and diarrhea.
These toxins disrupt the stomach and intestines and may even affect the liver or kidneys if absorbed into the bloodstream.
Toxin ingestion often results in sudden, violent vomiting and severe diarrhea.
Other symptoms include drooling, seizures, or tremors, depending on the type of toxin involved.
Related: Dog throwing up and diarrhea but acting normal
5. Pancreatitis
Pancreatitis is inflammation of the pancreas and is a serious condition that commonly causes both vomiting and diarrhea in dogs.
It often results from eating fatty foods or can be associated with underlying health conditions like obesity or diabetes.
A dog with pancreatitis may show signs like abdominal pain (shown as a hunched back), lethargy, fever, and vomiting combined with diarrhea.
Pancreatitis requires immediate veterinary care and possibly hospitalization.
6. Stress and Anxiety
Believe it or not, stress can upset your dog’s stomach.
Dogs may develop acute vomiting and diarrhea in response to environmental stressors such as moving to a new home, loud noises, separation anxiety, or changes in routine.
Stress affects the digestive system through hormone imbalances and changes in gut motility.
Dogs throwing up and having diarrhea due to stress may also exhibit behaviors like pacing, whining, or hiding.
7. Side Effects of Medication
Certain medications—especially antibiotics, nonsteroidal anti-inflammatory drugs (NSAIDs), or heartworm treatments—can cause side effects like vomiting and diarrhea.
These drugs may irritate the stomach lining or disrupt the balance of good bacteria in the gut.
If your dog develops symptoms shortly after starting a new medication, it’s important to notify your vet.
Never stop medication without professional guidance.
8. Chronic Conditions and Diseases
More serious health issues, such as inflammatory bowel disease (IBD), liver disease, or kidney failure, can present with ongoing vomiting and diarrhea.
These conditions often come with additional symptoms such as weight loss, poor coat condition, and increased drinking or urination.
Dogs with chronic digestive conditions may require long-term management and a specialized diet.
What to Do If Your Dog is Throwing Up and Has Diarrhea
When your dog shows signs of throwing up and diarrhea, your response depends on the severity and duration of symptoms. Here are some steps to take:
Monitor Symptoms
Keep an eye on the frequency, consistency, and color of the vomit and stool.
Note any additional signs like blood, mucus, or changes in appetite and behavior.
Withhold Food Temporarily
You can withhold food for 12–24 hours (but not water) to allow your dog’s stomach to settle.
This short fast gives the GI tract a break. Make sure your dog has access to clean water to prevent dehydration.
Offer Bland Food
After the fasting period, feed your dog a bland diet of plain boiled chicken and white rice in small portions.
Gradually reintroduce their regular food over several days once symptoms improve.
Provide Hydration
Dehydration is a major concern when a dog is throwing up and has diarrhea.
Offer small amounts of water frequently, or use unflavored electrolyte solutions made for pets.
Use Probiotics
Veterinary-recommended probiotics can help restore healthy gut flora and speed up recovery from digestive upset.
These are available in powder, capsule, or chewable forms.
When to Seek Veterinary Help
While mild cases may resolve with at-home care, some symptoms should prompt an immediate vet visit:
Frequent or severe vomiting and diarrhea that lasts more than 24 hours
Blood in vomit or stool, or black/tarry stools
Lethargy, unresponsiveness, or signs of pain
Fever, dehydration (dry gums, sunken eyes), or collapse
Known ingestion of toxic substances
If your puppy or senior dog is affected (they’re more vulnerable to rapid dehydration)
Chronic symptoms that persist or reoccur frequently
Your vet may perform blood tests, fecal exams, imaging, or even endoscopy to diagnose the cause and recommend treatment such as IV fluids, medications, or dietary changes.
Key Takeaway
Dog throwing up and diarrhea can be caused by many different things—from dietary issues to infections and underlying illnesses.
While mild cases may be manageable at home with a bland diet and hydration, ongoing or severe symptoms require veterinary attention.
Always monitor your dog’s condition closely and don’t hesitate to call your vet if symptoms worsen or persist.
Early diagnosis and treatment can make all the difference in your dog’s recovery and long-term health.
By staying informed and acting quickly, you can help your furry friend feel better and stay healthy.